Add test notification tool (#28334)

* Add test notification tool

* Add frontend styles

* Remove option from admin view

* Refactor create post and add translations

* Fix several CI errors

* Fix API and frontend snapshots

* Refactor trailing and leading icon on buttons

* Add different button states

* i18n-extract

* Fix wrong text

* Add tests

* Fix wrong string

* Fix test

* feat: E2E send test notifications (#28371)

* Refactor send desktop notification

* Address rest of the feedback

* Fix tests

* Add correct link

* Fix test

---------

Co-authored-by: Mattermost Build <build@mattermost.com>
Co-authored-by: yasserfaraazkhan <attitude3cena.yf@gmail.com>

server/public/model/post.go

@@ -75,6 +75,7 @@ const (
 	PostPropsMentionHighlightDisabled = "mentionHighlightDisabled"
 	PostPropsGroupHighlightDisabled   = "disable_group_highlight"
 	PostPropsPreviewedPost            = "previewed_post"
+	PostPropsForceNotification        = "force_notification"
 
 	PostPriorityUrgent               = "urgent"
 	PostPropsRequestedAck            = "requested_ack"
@@ -339,8 +340,9 @@ func (o *Post) EncodeJSON(w io.Writer) error {
 }
 
 type CreatePostFlags struct {
-	TriggerWebhooks bool
-	SetOnline       bool
+	TriggerWebhooks   bool
+	SetOnline         bool
+	ForceNotification bool
 }
 
 type GetPostsSinceOptions struct {
@@ -500,6 +502,7 @@ func (o *Post) SanitizeProps() {
 	}
 	membersToSanitize := []string{
 		PropsAddChannelMember,
+		PostPropsForceNotification,
 	}
 
 	for _, member := range membersToSanitize {